Get parent hierarchy from a child node in angular 6 material tree

Question

I am following a tutorial to implement cdk tree in angular 6. I created a tree structure, now I want to get the parent hierarchy from from the child by making it clickable, whil

Answer 1

Thanks to Flauwekeul, a little bit simplified

import { FlatTreeControl } from '@angular/cdk/tree';

export class CustomTreeControl extends FlatTreeControl {
  /**
   * Iterate over each node in reverse order and expand each inferior level nodes until level 0.
   */
  expandParents(node: any) {
      const currentLevel = this.getLevel(node);

      if (currentLevel < 1) {
          return null;
      }

      const startIndex = this.dataNodes.indexOf(node) - 1;

      for (let i = startIndex; i >= 0; i--) {
          const currentNode = this.dataNodes[i];

          if (this.getLevel(currentNode) < currentLevel) {
              this.expand(currentNode);
              if (this.getLevel(currentNode) === 0) break;
          }
      }
  }
}